The purpose of the demo version is to give a general look and feel of the software, it is not intended to show everything that the software can do.
The videos provide a middle ground and show the actual software features in operation with a real scope and actual signals. However for customers who need to actually try the scope in their specific environment, and with their signals, we offer a 14 day return guarantee http://www.picotech.com/orderinfo.html#warranty
in case the product does not meet their expectations.
You do not need a scope to download the software, and the links appear to be working, so if you are having issues then please contact email@example.com
and we can provide an alternative location for you to download the software from.